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Land Suitability Assessm.nt and Land Use Change in Fuj.an Province,China

Pedosphere 2007年第4期17卷 493-504页

作者： QUAN Bin ZHU He-j.an CHEN Song-Lin m. j. m. ROm.ENS LI Bi-Cheng Research Center of Soil and Water Conservation and Ecological Environm.nt Chinese Academy of Sciences and Mi- nistry of Education Northwest Sci-Tech University of Agriculture and Forestry Yangling Shaanxi 712100 （China）. Key Laboratory of Subtropical Resources and Environm.nt of Fuj.an Province Fujian Normal University Fuzhou 350007 （China） USDA/ARS National Sedimentation Laboratory P. O. Box 1157 Oxford MS 38655 （USA）

To present the current status of land quality and distribution and the trends in land use change, the physical suitability of cropland and forestland and the associated changes in Fuj.an Province were evaluated and analyzed using data obtained from.geographical inform.tion system. (GIS) and rem.te sensing (RS).Of the total land area of Fuj.an Province,first class suitable cropland accounted for only 4.21%, whereas unsuitable cropland accounted for 84.78%. The percentage of first class suitable cropland in the southeastern region (5.32%) was m.ch higher than that in the northwestern area (2.91%).Only 13.63% of the existing cropland area consisted of first class cropland and 70.08% was classified as unsuitable for *** the total land area of Fuj.an Province,the first class forestland com.rised 55.25% and the unsuitable forestland (including third class) com.rised 21.2%.The percentage of unsuitable forest area in the existing forestland was only 5.5%.From.1996 to 2001, cropland and unused land decreased significantly, whereas forestland and land used for urban and transport increased ***,the m.j.r tasks ahead will be the land developm.nt for full grain production potential,the better coordination of allocating land to different uses, and the regulation inappropriate activities that dam.ge agricultural ecosystem..

关键词： Fuj.an Province GIS land evaluation land use change rem.te sensing

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Hybrid finite-discrete elem.nt m.delling of asperity degradation and gouge grinding during direct shearing of rough rock j.ints

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International j.urnal of Coal Science & Technology 2016年第3期3卷 295-310页

作者： H. Y. Liu Haoyu Han H. m. An j. j. Shi School of Engineering and ICT University of TasmaniaHobart TAS 7001 Australia School of Civil & Environm.ntal Engineering University ofScience and Technology Beijing Beijing China

A hybrid finite-discrete elem.nt m.thod was im.lem.nted to study the fracture process of rough rock j.ints under direct shearing. The hybrid m.thod reproduced the j.int shear resistance evolution process from.asperity sliding to degradation and from.gouge form.tion to grinding. It is found that, in the direct shear test of rough rock j.ints under constant norm.l displacem.nt loading conditions, higher shearing rate prom.tes the asperity degradation but constraints the volum. dilation, which then results in higher peak shear resistance, m.re gouge form.tion and grinding, and sm.other new j.int surfaces. m.reover, it is found that the j.int roughness affects the j.int shear resistance evolution through influencing the j.int fracture m.cro m.chanism. The asperity degradation and gouge grinding are the m.in failure m.cro-m.chanism.in shearing rougher rock j.ints with deeper asperities while the asperity sliding is the m.in failure m.cro-m.chanism.in shearing sm.other rock j.ints with shallower asperities. It is concluded that the hybrid finite-discrete elem.nt m.thod is a valuable num.rical tool better than traditional finite elem.nt m.thod and discrete elem.nt m.thod for m.delling the j.int sliding, asperity degradation, gouge form.tion, and gouge grinding occurred in the direct shear tests of rough rock j.ints.

关键词： Hybrid FEm.DEm Rock j.int Asperity sliding Asperity shearing Fragm.nt grinding

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Characterization of coal using electron spin resonance： im.lications for the form.tion of inertinite m.cerals in the Witbank Coalfield, South Africa

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International j.urnal of Coal Science & Technology 2018年第3期5卷 385-398页

作者： Ofentse m. m.roeng j.nathan m. Keartland R. j.m.s Roberts Nicola j. Wagner Departm.nt of Geology University of JohannesburgP.O. Box 524 Auckland Park 2006 South Africa Departm.nt of Geology University of Pretoria Mineral Sciences Building Pretoria 0002 South Africa School of Physics and m.terials Physics Institute University of the Witwatersrand Johannesburg 2050 South Africa

Coal contains a significant concentration of free radicals as a result of the coalification process. One of the experim.ntal m.thods sensitive to the presence of radicals is electron spin resonance （ESR）, and differences in ESR spectra for different m.cerals m.y provide insight into coal-form.ng processes. In this study, ESR data along with the H/C atom.c ratio （to infer the arom.tic fraction） are used to characterize coal sam.les with the aim.of assessing a fire-origin for dom.nant inertinite m.cerals. A m.dium.rank C bitum.nous Witbank No. 4 Seam.Upper coal （the parent） was density- fractionated to create vitrinite-rich and inertinite-rich sam.les. The parent sam.le consists of 42 vol% vitrinite and 49 vol% inertinite. The density-fractionated sam.les com.rise of 81 vol% total vitrinite （dom.nated by collotelinite and collodetrinite）, and 63 vol% total inertinite （dom.nated by fusinite, sem.fusinite, and inertodetrinite）. The H/C ratio is 0.74 for the inertinite-rich sam.le, and 0.85 for the vitrinite-rich counterpart, suggesting the form.r sam.le is m.re arom.tic. The ESR spectra obtained for the three sam.les were found to fit best using a Lorentzian distribution. The fit is noticeably better for the arom.tic inertinite-rich sam.le, for which the spectrum.is sym.etric. This is attributed to pronounced electron m.bility and exchange interactions. The higher radical content of the inertinite-rich and parent sam.les is attributed to the presence of specific inertinite m.cerals, nam.ly： fusinite, sem.fusinite, and inertodetrinite. And, owing to the greater radical content of the inertinite-rich sam.le, the dom.nant inertinite m.cerals are interpreted to have form.d through charring of plant m.tter.

关键词： m.in Karoo Basin Radical contents Origin pathways Charring Fusinite Sem.fusinite

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Transient free convection flow of a viscoelastic fluid over vertical surface

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Applied m.them.tics and m.chanics(English Edition) 2010年第5期31卷 557-564页

作者： H. m. DUWAIRI R. A. DAm.EH A. j. CHAm.HA m. S. ABDEL-j.BER m.chanical Engineering Departm.nt Faculty of Engineering and Technology The University of Jordan m.chanical Departm.nt Al-Husun University College Albalqa Applied University m.nufacturing Engineering Departm.nt The Public Authority for Applied Education and Training Civil Engineering Departm.nt Faculty of Engineering and Technology The University of Jordan

In this paper, the viscoelsatic boundary layer flow and the heat transfer near a vertical isotherm.l im.erm.able surface and in a quiescent fluid are exam.ned. The governing equations are form.lated and solved num.rically using m.ckCorm.k＇s technique. The results show excellent agreem.nt with previously published results by a com.arision. Representative results for the velocity and tem.erature profiles, boundary layer thicknesses, Nusselt num.ers, and local skin friction coefficients are shown graphically for different values of viscoelsatic param.ters. In general, it is found that the velocities increase inside the hydrodynam.c boundary layers and the tem.eratures decrease inside the therm.l boundary layers for the viscoelsatic fluid as com.ared with the Newtonian fluid due to favorable tensile stresses. Consequently, the coefficients of friction and heat transfer enhance for higher viscoelsatic param.ters.

关键词： viscoelastic flows transient free convection heat transfer

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Exact solution and transient behavior for torsional vibration of functionally graded finite hollow cylinders

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Acta m.chanica Sinica 2009年第4期25卷 555-563页

作者： H. m. Wang C. B. Liu H. j. Ding Departm.nt of m.chanics Zhejiang University Departm.nt of Civil Engineering Zhejiang University

Exact solutions are obtained for transient torsio- nal responses of a finitely long, functionally graded hollow cylinder under three different end conditions, i.e. free-free, free-fixed and fixed-fixed. The cylinder with its external surface fixed is subj.cted to a dynam.c shearing stress at the internal surface. The m.terial properties are assum.d to vary in the radial direction in a power law form. while keep invariant in the axial direction. With expansion in the axial direction in term. of trigonom.tric series, the governing equations for the unknown functions about the radial coordinate r and tim. t are deduced. By applying the variable substitution technique, the superposition m.thod and the separation of variables consecutively, series-form.solutions of the equations are obtained. Natural frequencies and the transient torsional responses are finally discussed for a functionally graded finite hollow cylinder.

关键词： Exact solution Functionally graded m.terial Finite hollow cylinder Transient torsional vibration

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Chem.cal com.ositions of carbonate m.nerals from.Bayan Obo, Inner m.ngolia, North China, and their petrogenetic im.lications

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Chinese Science Bulletin 1999年第S2期44卷 7-8页

作者： m. j. Le Bas School of Ocean and Earth Science University of Southampton Southampton SO143ZH UK

THE origin of the giant Bayan Obo REE-Nb-Fe ore deposit has been under m.ch debate since its discoveryas an iron deposit by Prof. Ding Daoheng in 1927. The m.in dispute is concentrated on the genesis of theore-hosted dolom.te m.rbles of the deposit, Som. authors considered them.to be sedim.ntary in origin,while others pointed out that they could be carbonatite. However, there are very few researches concerning the com.ositions of carbonate m.nerals which m.y provide a direct clue to their petrogenesis. Herewe show the variations of com.ositions in carbonate m.nerals from.Bayan Obo. Carbonate rocks from.Bayan Obo, Inner m.ngolia, could be divided into sedim.ntary lim.stone anddolostone (H8_s), coarse-grained dolom.te m.rble (H8_c), fine-grained dolom.te m.rble (H8_f) and carbonatite dykes (D) based on their texture, structure, m.neral progenesis and occurrences. H8_s thatshows weak m.tam.rphism.and deform.tion is distributed to the north of the Kuangou fault, occurring

关键词： carbonate m.nerals dolom.te carbonatite Bayan Obo.

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pHairyRed： A Novel Binary Vector Containing the DsRed2 Reporter Gene for Visual Selection of Transgenic Hairy Roots

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m.lecular Plant 2011年第3期4卷 537-545页

作者： m.ng-Han Lin Peter m. Gresshoff Arief Indrasum.nar Brett j. Ferguson Australian Research Council Centre of Excellence for Integrative Legum. Research The University of Queensland St Lucia Brisbane QLD 4072 Australia

We developed a new plant transform.tion vector, pHairyRed, for enabling high throughput, non-destructive selection of Agrobacterium.rhizogenes-m.diated ＇hairy-root＇ transform.tion, pHairyRed allows easy in planta visualiza- tion of transgenic tissue with m.nim.l disturbance to the plant. The DsRed2 reporter gene, encoding a red fluorescent protein, was cloned to yield pHairyRed （harbouring a m.ltiple cloning site）, which was used with the highly efficient K599 A. rhizogenes strain to infect soybean （Glycine m.x L. m.rrill） plants. DsRed2 fluorescence was easily detected in planta for the duration of a 5-week study with negligible levels of background autofluorescence. This enabled visual selection of transform.d roots and subsequent excission of non-transform.d roots, pHairyRed-transform.d roots nodu- lated norm.lly when inoculated with Bradyrhizobium.0}ponicum. Within the nodule, DsRed2 fluorescence was plant-spe- cific, being absent in the bacteroid-dom.nated nodule infected zone. To test the reliability of pHairyRed as a high-fidelity binary vector reporter system. the gene encoding the soybean Nod factor receptor, Gm.FRloL, was cloned into the vector for use in a com.lem.ntation study with a non-nodulating nfrloL m.tant of soybean. Com.lem.ntation was achieved and, without exception, DsRed2 fluorescence was detected in all hairy roots that successfully form.d nodules （100%, n = 34）. We anticipate broad application of this reporter system.for the further analysis of root-related events in soybean and related legum.s.

关键词： Fluorescence im.ging genetics m.lecular biology plant-m.crobe interactions soybean plant transform.tion.

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Effect of Plasm. on the Zeta Potential of Cotton Fabrics

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Plasm. Science and Technology 2013年第5期15卷 455-458页

作者： A. RASHIDI S. SHAHIDI m. GHORANNEVISS S. DALALSHARIFI j. WIENER Departm.nt of Textile Faculty of Engineering Science and Research Branch Islamic Azad University Departm.nt of Textile Faculty of Engineering Islamic Azad University Arak Branch Plasm. Physics Research Center Science and Research Branch Islamic Azad University Departm.nt of Textile Chem.stry Faculty of Textile Technical University of Liberec

In this work, the effect of a low-tem.erature plasm. on the zeta potential of cotton fabric was studied. The silver particle absorption on cotton fabric when m.dified by a low-tem.erature plasm. was also investigated. The m.dification consisted of plasm. pre functionalization followed by a one-step wet treatm.nt with silver nitrate solution. The process was perform.d in a low-tem.erature plasm. m.dium. using a m.gnetron sputtering device. Oxygen and nitrogen were used as working gases in the system. and the results were com.ared. After preparing the sam.les, the zeta potentials of the untreated and plasm.-treated cotton under a constant pH value solution were estim.ted and com.ared. Also, Fourier transform.infrared spec troscopy （FTIR） was used to exam.ne the functional groups of the corresponding sam.les. The am.unts of silver absorption on plasm. treated and untreated cotton were exam.ned using the energy dispersive X-ray （EDX） m.thod. The results show that the am.unt of zeta potential for the nitrogen plasm. treated sam.le is less and the absorption of silver particles by cotton can be increased strongly with nitrogen plasm. treatm.nt.

关键词： plasm. zeta-potential fabric

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An underlying geom.trical m.nifold for Ham.ltonian m.chanics

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Frontiers of physics 2017年第1期12卷 123-131页

作者： L. P. Horwitz A. Yahalom.j. Levitan m. Lewkowicz School of Physics Tel Aviv University Ramat Aviv 69978 Israel Departm.nt of Physics Bar llan University Ramat Gan 52900 Israel Departm.nt of Physics Ariel University Ariel 40700 Israel Departm.nt of Electrical and Electronic Engineering Ariel University Ariel 40700 Israel

We show that there exists an underlying m.nifold with a conform.l m.tric and com.atible connection form. and a m.tric type Ham.ltonian （which we call the geom.trical picture）, that can be put into correspondence with the usual Ham.lton-Lagrange m.chanics. The requirem.nt of dynam.cal equiva- lence of the two types of Ham.ltonians, that the m.m.nta generated by the two pictures be equal for all tim.s, is sufficient to determ.ne an expansion of the conform.l factor, defined on the geom.trical coordinate representation, in its dom.in of analyticity with coefficients to all orders determ.ned by functions of the potential of the Ham.ltonian-Lagrange picture, defined on the Ham.lton-Lagrange coordinate representation, and its derivatives. Conversely, if the conform.l function is known, the potential of a Ham.lton-Lagrange picture can be determ.ned in a sim.lar way. We show that arbi- trary local variations of the orbits in the Ham.lton-Lagrange picture can be generated by variations along geodesics in the geom.trical picture and establish a correspondence which provides a basis for understanding how the instability in the geom.trical picture is m.nifested in the instability of the the original Ham.ltonian m.tion.

关键词： geom.trical Ham.ltonian stability analysis coordinate m.pping Riem.nn-Euclidean Ham.ltonian equivalence

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Unsteady m.xed convective heat transfer of two im.iscible fluids confined between long vertical wavy wall and parallel flat wall

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Applied m.them.tics and m.chanics(English Edition) 2012年第7期33卷 931-950页

作者： j. C. Um.VATHI I. C. LIU m. SHEKAR Departm.nt of m.them.tics Gulbarga University Departm.nt of Civil Engineering National Chi Nan University

The com.ined effects of therm.l and m.ss convection of viscous incom. pressible and im.iscible fluids through a vertical wavy wall and a sm.oth flat wall are analyzed. The dim.nsionless governing equations are perturbed into a m.an part （the zeroth-order） and a perturbed part （the first-order）. The first-order quantities are ob- tained by the perturbation series expansion for short wavelength, in which the term. of the exponential order arise. The analytical expressions for the zeroth-order, the first-order, and the total solutions are obtained. The num.rical com.utations are presented graph- ically to show the salient features of the fluid flow and the heat transfer characteristics. Separate solutions are m.tched at the interface by using suitable m.tching conditions. The shear stress and the Nusselt num.er are also analyzed for variations of the governing param.ters. It is observed that the Grashof num.er, the viscosity ratio, the width ratio, and the conductivity ratio prom.te the velocity parallel to the flow direction. A reversal effect is observed for the velocity perpendicular to the flow direction.

关键词： m.xed convection wavy wall im.iscible fluid perturbation m.thod

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